1. Field of the Invention
This invention relates to a device that utilizes the linear relationship between the electrical current and the torque of the D.C. motor to simulate the effect of a weight stack of exercise machines. Its simple construction, ease in adjustment and noiseless operation and the ability to change its load and to program the exercise curve through an electronic controller making exercise easier and more comfortable.
2. Prior Art
But relating to the prior art (U.S. Pat. No. 5,304,104), same defects still exist:
1. When the load is low, the loss of system's inertia and friction causes the rewinding of cable slowdown or even stopped, therefore simulation of the feel of conventional weight stack and other exercise devices is not attainable. PA1 2. When the system power is turned off or when the power is broken down during use, slack of the cable appears as the motor loses its rewinding force which can easily result in the cable slipping off the spiral groove of the winding drum.